Access control is an important problem with many applications. One application for access control is where a facility contains a plurality of secure facilities, offices and compartments, each belonging to a particular person; i.e. each person only needs access to the particular facilities, offices and compartments authorized for them, not any of the other ones. Typically, this is done with a card system; each person has an access card, and the system comprises card readers that have no intelligence built in, and an access control panel, comprising hardware and software that enrolls cards into the access control system and assigns access privileges and other user information to each one. The card reader transfers the card number to the access control panel by using a Wiegand interface; a database then stores the access card number for each user, and any other information related to the user.
Biometric access is much simpler for a user than card access; however, to retrofit biometrics into an existing card-based access control system, two databases are required. One is the conventional access card number database which contains user information, card number assigned to each user, and user privileges, and the other database is one that contains biometric information for each enrolled user as well as user information and user privileges and correlates it to the user's access card number. This requires integration, or bridging between two databases, which is a complex procedure; it means that enrollment in one database should trigger the other database to create the same event. This procedure is memory-intensive and consumes a lot of computing power. Integrating the database completely requires the creation of additional fields for biometric credentials and biometric reader service information which makes the combined database larger and more complicated.
Furthermore, the enrollment procedure for a biometric access control system is more complex, involving obtaining and storing the user's biometric information in a separate data base.
A need exists for a biometric reader that can generate a unique number similar in format to an access card number and transmit it through a Wiegand interface to the access panel.
A need also exists for a biometric reader that generates a unique biometric credential that can be recognized as valid by an access control panel without any storage or retrieval of biometric information.